Visfatin (also known as PBEF and Namp) is an enzyme that in humans is encoded by the PBEF1 gene. This protein has also been reported to be a cytokine (PBEF) that promotes B cell maturation and inhibits neutrophil apoptosis. It is downregulated by an increase of miR-34a in obesity via a 3'UTR functional binding site of NAMPT mRNA resulting in a reduction of NAD (+) and decreased SIRT1 activity.Sample Type:Serum and plasmaIntended Use:The kit is a competitive enzyme immunoassay for the in vitro quantitative measurement of Visfatin in human serum, plasma; and other biological fluids not being tested.Sensitivity:130pg/mlRange:9.8-40,000pg/mlSpecificity:This assay has high sensitivity and excellent specificity for detection of human Visfatin.Precision:Intra CV<10%; Inter CV <15%Test Principle:The immunoplate in this kit is pre-coated with secondary antibody and the nonspecific binding sites are blocked. The secondary antibody can bind to the Fc fragment of the visfatin antibody whose Fab fragment will be competitively bound by both biotinylated Visfatin peptide and peptide standard or targeted peptide in samples. The biotinylated Visfatin peptide interacts with streptavidin-horseradish peroxidase (SA-HRP) which catalyzes TMB substrate solution. The intensity of the yellow is directly proportional to the amount of biotinylated Visfatin peptide SA-HRP complex but inversely proportional to the amount of the peptide in standard solutions or samples. A standard curve of known Visfatin concentration can be established accordingly. The unknown Visfatin concentration in samples can be determined by extrapolation to this standard curve.Kit Components:Assay plate (12x8 coated Microwells)-1Primary antibody-2x6uLStandard peptide-2x10uLBiotinylated peptide-2x10uLHRP-Streptavidin concentrate-1x 60uLAssay diluent (5x concentrate)-1x15mLWash buffer (20x concentrate)-1x 25mLTMB substrate-1x12mLStop solution-1x8mLAdhensive strip-2Instruction manual-1.Storage and Stability:Store powder at 4°C liquid at -20°C. Store other components at 4°C. Stable for at least 6 months For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
